Manually operated pump utilizing backpressure for easement of pump stroke

ABSTRACT

Diving apparatus employing a hand operated pump is disclosed. The apparatus is characterized by a hand operated pump for supplying air to a user consisting of a chamber provided with a piston which is connected via piston rod to a handle and a slide valve is associated with the piston rod. The slide valve is provided with passages or grooves which , with the valve in its innermost position, provide communication between a discharge port and the region between the valve and piston (back side of piston); and with the valve in its outermost position, provide communication between an inlet port and the back side of the piston. The chamber is also provided with second inlet and discharge ports at a point most remote from the slide valve, whereby fresh air is directed to the user via second inlet and discharge ports, and exhausted air is directed through a flexible hose and then to the back side of the pump piston pressurizing the same thereby balancing the piston load and reducing the effort required to stroke the pump.

United States Patent 1 Jordan [451 July 31,1973

[76] Inventor: Donald .I. Jordan, 113 Evergreen Ln., Glastonbury, Conn. 06033 [22] Filed: Jan. 3, 1972 [21] Appl. No.1 215,040

[52] US. Cl 417/323, 417/392, 128/145,

128/145.7 [51] Int. Cl. F04c 9/00 [58] Field of Search l28/l45.7, 145.8,

Primary Examiner-Richard A. Gaudet Assistant Examiggr l-Ienry J. Recla A ttorney- David S. Fishman and Roger A. Van Kirk [57] ABSTRACT Diving apparatus employing a hand operated pump is disclosed. The apparatus is characterized by a hand operated pump for supplying air to a user consisting of a chamber provided with a piston which is connected via piston rod to a handle and a slide valve is associated with the piston rod. The slide val v e is provided with passages or grooves which, with the valve in its innermost position, provide communication between a discharge port and the region between the valve and piston (back side of piston); and with the valve in its outermost position, provide communication between an inlet port and the back side of the piston. The chamber is also provided with second inlet and discharge ports at a point most remote from the slide valve, whereby fresh air is directed to the user via second inlet and discharge ports, and exhausted air is directed through a flexible hose and then to the back side of the pump piston pressurizing the same thereby balancing the piston load and reducing the effort required to stroke the pump.

8 Claims, 2 Drawing Figures Patented July 31, 1973 MANUALLY OPERATED PUMP UTILIZING BACKPRESSURE FOR EASEMENT OF PUMP STROKE BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to underwater diving apparatus. More specifically, this invention is directed to the supplying of breathable gas from the surface to an underwater diver. Accordingly, the general objects of the present invention are to provide novel and improved apparatus and methods of such character.

2. Description of the Prior Art At present underwater diving apparatus falls within two general categories. Although the name is somewhat misdescriptive, the first of these categories, and the one with which the present invention is concerned, is known as hard hat diving. The second category of prior art diving apparatus encompasses the selfcontained or SCUBA diving equipment. Both general types of prior art diving equipment have advantages and disadvantages. The disadvantages are amplified in the case of shallow diving. In the context of this application, shallow diving refers to working at depths up to approximately 20 feet.

Among the principal disadvantages of both types of prior art diving equipment are comparative complexity, which has an undesirable effect on reliability, and relatively high cost. In the case of hard hat diving, where the diver is supplied with air from the surface, the components which are most subject to failure and make the largest contribution to both the cost and the complexity of the equipment are those which pressurize air and thereafter deliver the pressurized air to the diver. In order to deliver air to a diver feet below the surface it is necessary to pump the air against the pressure of approximately 6 psi. To pump the required amount of air against this pressure requires more power than man can normally provide for a reasonable period of time. Accordingly, hand pumps are not now used and more complicated motor-driven equipment is required.

SUMMARY OF THE INVENTION The present invention overcomes the above-briefly discussed and other disadvantages and deficiencies of the prior art by providing a novel and improved diving device which is less complicated, more reliable and less expensive than prior art equipment of like character. In achieving the foregoing objectives the invention provides a novel method of reducing the amount of power required to drive a hand pump associated with a diving device to a level that can easily be provided by a normal person.

In accordance with a preferred embodiment the invention comprises a novel hand operated pump, including an integral valve, which will be located above the surface and connected to the divers apparatus by a pair of flexible hoses. The divers apparatus will include a mouth piece and a flexible bag coupled thereto. A particularly novel feature of the invention is the use of air after it has been discharged by the diver. Rather than being exhausted under the water as is now the practice, the discharged air, still under pressure, is directed back to the surface through one of the flexible hoses and is used to pressurize the back side of the pump piston thereby balancing the piston load and reducing the effort required to stroke the pump.

BRIEF DESCRIPTION OF THE DRAWING The present invention may be better understood and its numerous objects and advantages will become apparent to those skilled in the art by reference to the accompanying drawing wherein like reference numerals refer to like elements in the several figures and in which:

FIG. 1 is a cross-sectional view of a preferred embodiment of the present invention, FIG. 1 depicting the pump at the beginning of the suction stroke; and

FIG. 2 depicts the apparatus of FIG. 1 with the pump shown at the initiation of the pressure stroke.

DESCRIPTION OF THE PREFERRED EMBODIMENT In accordance with the present invention a hand operated pump, indicated generally at 10, is employed to deliver pressurized air to a divers mouthpiece 12. The variable volume chamber 14 of pump 10 is connected directly to mouthpiece 12 via a flexible conduit 15. Mouthpiece 12 is tubular and is coupled, via a branch conduit 16, to a flexible bag 18. Flexible bag 18 is in turn connected back to pump 10 by a second flexible conduit 20 and a pump port 21; coupling between bag 18 and conduit 20 being achieved via a T fitting 22 which is provided with a check valve 24.

Pump 10 is provided with a piston 26 which is connected, via piston rod 28, to a handle 30. Operation of the pump is accomplished by stroking handle 30 thus moving the piston 26 longitudinally of chamber 14. A pair of pins 32 and 34 extend through and are attached to the piston rod 28 of pump 10. Pin 32 and 34 cooperate, in the manner to be described below, with a slide valve and determine the limits of movement of piston 26. Pump 10 further comprises a pair of check valves 36 and 38 which respectively provide communication between the atmosphere and chamber 14 and conduit 15 and chamber 14. As will be explained in more detail below, check valve 36 will open as the pump piston 26 is moved to the right as shown in FIG. 1 thereby providing communication between an inlet port 40 and chamber 14. Check valve 38 will open during the delivery stroke with piston 26 moving to the left, thereby providing communication between a discharge port 42 and conduit 15.

The pump 10 is also provided with a slide valve defined by valve member 44. The valve member 44 is provided with passages or grooves 46 and 48 which, with the valve in the position shown in FIG. 1, provide communication between the region 50 of chamber 14 behind piston 26 and a second discharge port 52. Valve member 44 is slidably mounted on piston rod 28 and will be moved between the positions shown in FIGS. 1 and 2 respectively by pins 34 and 32. The limits of motion of piston 26 are defined by contact between internal shoulders 54 and 56 on the pump housing and valve member 44.

In operation, during the suction stroke the pump piston 26 is moved to the right by pulling on pump handle 30. This causes air to be drawn into chamber 14 through check valve 36 and inlet port 40. At this time check valve 38 is closed by suction. Used air previously delivered, in the manner to be described below, to the portion 50 of chamber 14 behind piston 26 will be forced out through the passages 46 and 48 in valve member 40 and will be discharged to the atmosphere through port 52. During the suction stroke port 21 will also be shut since valve member 44 will be in the position shown in FIG. 1. Accordingly, pressure is maintained at the mouth piece 12 and the diver breathes air previously stored in the flexible bag 18. lt is particularly to be noted that valve member 44 will remain stationary during the early stage of the suction stroke; i.e., until it is contacted by pin 32.

Toward the end of the suction stroke pin 32 will contact valve member 44 and will move the valve member to the position shown in FIG. 2. The rearward limit of motion of piston 26 will be determined by contact between valve member 44 and shoulder 56.

On the pressure or delivery stroke the piston 26 will be moved to the left by pushing on handle 30. Air drawn into chamber 14 during the suction stroke will be forced through check valve 38 and, via flexible conduit 15, down to the mouth piece 12 and flexible bag 18. During the pressure stroke the used air in flexible bag 18 will be forced out through connector 22 and flexible conduit 20. The used air will enter pump chamber 14 behind piston 26 via connector 21 and passages 48 and 46 in valve member 44. Accordingly, during the pressure stroke both sides of piston 26 will be exposed to approximately the same pressure and the force required to stroke the pump is very low. As shown in FIG. 2, during the pressure stroke discharge port 52 will be closed by valve member 44 and, of course, check valve 36 will also be closed by the pressurized air ahead of the pump piston.

During the pressure or delivery stroke of pump a slightly greater volume of air will be expelled from chamber .14 than is required to fill the portion 50 of the pump chamber behind piston 26. This results from the fact that chamber portion 50 is partially filled by the piston rod 28. The excess air will be discharged through check valve 24 located in connector 22 and thus check valve 24 will establish the pressure level inbag l8 and the pressure available to the diver at the mouthpiece l2. Near the end of the pressure stroke pin 34 will contact valve member 44 and will cause the slide valve to return to the FIG. 1 position.

The volume of pump chamber 14 and the number of strokes per minute will be established at a level that will provide adequate pressure to the diver. Since the pump pressure will be low for moderate depths, the entire apparatus may be fabricated from relatively low cost plastic and rubber materials. Accordingly, the present invention provides a simple, reliable and inexpensive shallow diving apparatus.

While a preferred embodiment has been shown and described, various modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustration and not limitation.

What is claimed is:

l. Fluid supplying apparatus comprising:

pump means, said pump means including a housing defining a cylinder and a piston reciprocally movable therein;

means for delivering fluid from said pump means cylinder at one side of said piston to a fluid consuming load when said piston is moved in a first direction, said delivering means interrupting communication between the cylinder and load except when said piston is moved in said first direction;

means for supplying fluid to said pump means cylinder at said one side of said piston when said piston is moved in the second direction; said supplying means preventing delivery of fluid to said cylinder when fluid is being supplied to a load;

means for storing pressurized fluid previously delivered from said pump means to the load; and

means connected between said storing means and said pump means for returning pressurized fluid to said pump cylinder at the second side of said piston during movements of said piston in said first direction, said returning means isolating said storing means from said cylinder during movements of said piston in said second direction.

2. The apparatus of claim 1 wherein said supplying apparatus is employed to furnish air to a diver and wherein said means for returning fluid to said pump cylinder comprises:

an extension of said pump means housing, said extension defining a valve body having a channel which communicates with said pump means cylinder, said extension further defining an inlet port and a discharge port for said channel; slide valve positioned in said housing extension channel, said slide valve in a first position establishing communication between said cylinder at said second side of said piston and said extension inlet port said slide valve in a second position establishing communication between said extension discharge port and said piston means cylinder at said second side of said piston; and

flexible hose means for connecting said storing means to said housing extension inlet port.

3. The apparatus of claim 2 wherein said pump means further comprises:

a piston rod attached to said piston and extending through said housing extension channel, said piston rod also passing through and being slidable with respect to said slide valve;

means mounted on said piston rod for engaging and causing movement of said slide valve between said first and second positions, said engaging means being spacially displaced and respectively engaging said slide valve when said piston approaches its limits of motion in said first and second directions.

4. The apparatus of claim 3, wherein said apparatus further comprises:

a mouthpiece; and wherein said storing means comprises:

flexible bag means connected to said mouthpiece and said flexible hose.

5. The apparatus of claim 4 wherein said delivering means comprises:

an exit port in said pump means cylinder;

a check valve mounted in said exit port; and

flexible hose means coupling said exit port downstream of said check valve to said mouthpiece.

6. The apparatus of claim 5 wherein said supplying means comprises:

an inlet port in said piston means housing; and

a check valve disposed in said inlet port upstream of I said cylinder.

7. The apparatus of claim 6 wherein said housing exmeans operatively coupled to said means for returnat the same pressure as the pump fluid supply during pressurized fluid to said pump cylinder at the ing movements of said piston in said second direcsecond side of said piston for connecting said pump tion.

cylinder at said piston second side to a fluid source 

1. Fluid supplying apparatus comprising: pump means, said pump means including a housing defining a cylinder and a piston reciprocally movable therein; means for delivering fluid from said pump means cylinder at one side of said piston to a fluid consuming load when said piston is moved in a first direction, said delivering means interrupting communication between the cylinder and load except when said piston is moved in said first direction; means for supplying fluid to said pump means cylinder at said one side of said piston when said piston is moved in the second direction; said supplying means preventing delivery of fluid to said cylinder when fluid is being supplied to a load; means for storing pressurized fluid previously delivered from said pump means to the load; and means connected between said storing means and said pump means for returning pressurized fluid to said pump cylinder at the second side of said piston during movements of said piston in said first direction, said returning means isolating said storing means from said cylinder during movements of said piston in said second direction.
 2. The apparatus of claim 1 wherein said supplying apparatus is employed to furnish air to a diver and wherein said means for returning fluid to said pump cylinder comprises: an extension of said pump means housing, said extension defining a valve body having a channel which communicates with said pump means cylinder, said extension further defining an inlet port and a discharge port for said channel; a slide valve positioned in said housing extension channel, said slide valve in a first position establishing communication between said cylinder at said second side of said piston and said extension inlet port said slide valve in a second position establishing communication between said extension discharge port and said piston means cylinder at said second side of said piston; and flexible hose means for connecting said storing means to said housing extension inlet port.
 3. The apparatus of claim 2 wherein said pump means further comprises: a piston rod attached to said piston and extending through said housing extension channel, said piston rod also passing through and being slidable with respect to said slide valve; means mounted on said piston rod for engaging and causing movement of said slide valve between said first and second positions, said engaging means being spacially displaced and respectively engaging said slide valve when said piston approaches its limits of motion in said first and second directions.
 4. The apparatus of claim 3, wherein said apparatus further comprises: a mouthpiece; and wherein said storing means comprises: flexible bag means connected to said mouthpiece and said flexible hose.
 5. The apparatus of claim 4 wherein said delivering means comprises: an exit port in said pump means cylinder; a check valve mounted in said exit port; and flexible hose means coupling said exit port downstream of said check valve to said mouthpiece.
 6. The apparatus of claim 5 wherein said supplying means comprises: an inlet port in said piston means housing; and a check valve disposed in said inlet port upstream of said cylinder.
 7. The apparatus of claim 6 wherein said housing extension is provided with a pair of spacially displaced stops for limiting the motion for said slide valve.
 8. The apparatus of claim 1 further comprising: means operatively coupled to said means for returning pressurized fluid to said pump cylinder at the second side of said piston for connecting said pump cylinder at said piston second side to a fluid source at the same pressure as the pump fluid supply during movements of said piston in said second direction. 